Skip to content

CI Egress Allowlist

This page documents the network endpoints CI jobs are allowed to reach when step-security/harden-runner is operating in block mode. Managed under #878.

Status

All 76 jobs across the 28 workflow files in .github/workflows/ are currently in audit mode — harden-runner is the first step in every job and records outbound network calls to the step-security telemetry dashboard but does not block them.

The next iteration (tracked as a follow-up under #878) flips each group to block once the audit-mode runs confirm the allowlist is complete. Switching one job at a time keeps blast radius small: a missing endpoint on a block-mode job fails the run loud and the list below gets updated.

Allowlist (by domain)

This is the union of endpoints the entire workflow surface needs. When flipping a specific job to block mode, narrow this list to the endpoints that particular job actually touches.

GitHub itself (universally required)

Endpoint Used by Why
github.com:443 every job git clone, gh CLI
api.github.com:443 every job gh CLI, issue/PR API
objects.githubusercontent.com:443 every job release-asset downloads, LFS objects
*.actions.githubusercontent.com:443 every job runner ↔ orchestrator
pkg.actions.githubusercontent.com:443 every job action-cache CDN
results-receiver.actions.githubusercontent.com:443 every job workflow telemetry
codeload.github.com:443 jobs that git clone tagged refs tarball downloads for some actions
uploads.github.com:443 jobs that upload artifacts actions/upload-artifact
raw.githubusercontent.com:443 the install-script jobs curl-pull of unversioned content

Package managers (apt, brew, cargo, npm, luarocks)

Endpoint Used by Why
azure.archive.ubuntu.com:443 ubuntu jobs running apt-get apt mirror
archive.ubuntu.com:80 ubuntu jobs running apt-get apt mirror
security.ubuntu.com:80 ubuntu jobs running apt-get security updates
keyserver.ubuntu.com:443 jobs that add repo signing keys GPG keyserver
formulae.brew.sh:443 macOS jobs running brew Homebrew formula index
ghcr.io:443 + *.docker.io:443 docker / container jobs image pulls
registry.npmjs.org:443 npm-publish.yml + the pre-commit npm hook npm metadata + publish
registry-1.docker.io:443 docker jobs image manifests
crates.io:443 + static.crates.io:443 cargo-install jobs crate downloads
index.crates.io:443 cargo-install jobs crate index
luarocks.org:443 + *.luarocks.org:443 reusable-lua-lint.yml luacheck install

Project-specific installers (chezmoi / mise / starship / stylua / typos / etc.)

Endpoint Used by Why
get.chezmoi.io:443 setup-chezmoi composite (fallback path) chezmoi installer
mise.run:443 setup-mise composite mise installer
releases.starship.rs:443 mise-managed install of starship starship binary

Security / SBOM / scanning

Endpoint Used by Why
api.osv.dev:443 grype / scorecard OSV vuln database
vulners.com:443 grype vulnerability metadata
toolbox-data.anchore.io:443 anchore/sbom-action SBOM tooling
api.deps.dev:443 future deps.dev integration (#877) package metadata
api.securityscorecards.dev:443 scorecard.yml publish_results upload
*.codeql.github.com:443 codeql.yml CodeQL bundle download

Job-level egress notes (legitimate broad-egress jobs)

A few jobs need wider network access than the standard allowlist covers. Each carries an inline comment near the harden-runner step explaining the deviation so reviewers can audit at a glance.

update-deps.yml — broad GitHub API egress

Polls multiple github.com/<repo>/releases/latest endpoints to find new tool versions. Allowlist needs to include api.github.com:443 and the raw-content domain for sed-replacing version strings.

devcontainer-prebuild.yml — registry push

Pushes to ghcr.io:443 with the packages: write token. The egress allowlist for that job is the standard set plus ghcr.io writes.

nightly.yml — Beta/Nightly Tools Test job

This job deliberately runs curl ... | tar -xJf - against the shellcheck release. Justified because the job is continue-on-error: true and is opt-in (manual or scheduled). Future hardening: download the release asset, verify a known hash, then exec — same shape as tools/ci/install-chezmoi-verified.sh.

Updating this page

Whenever a job is flipped to block mode:

  1. Run the audit-mode workflow at least once after every recent workflow change to make sure the harden-runner telemetry reflects reality.
  2. Visit the step-security dashboard filtered to the repo + job + last 7 days.
  3. Add any endpoints the dashboard reports that aren't already in this page's tables.
  4. Edit the job to set egress-policy: block and add the per-job allowed-endpoints: block listing only what that specific job needs (not the whole union).
  5. Land the change, watch the first run; if anything fails the run loud, add the missing endpoint and retry.

References